#243A4E
Closest named color: Dark Blue Grey (#1F3B4D). oklch(34% 0.045 247), rgb(36, 58, 78).
Aa
White text reads best on this color (11.73:1).
About this color
#243A4E is a dark, muted blue. In OKLCH its lightness is 34%, its chroma 0.045 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.007 away. White text reads best on it, at 11.73:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | muted (0.045) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.79:1 |
| White text | 11.73:1 |
Values
| HEX | #243A4E |
| RGB | rgb(36, 58, 78) |
| HSL | hsl(209, 37%, 22%) |
| OKLCH | oklch(34% 0.045 247) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #243A4E | 11.73:1 | AAA | Lc -100.5 | Preferred for body text |
| Black text on #243A4E | 1.79:1 | Fails | Lc 0.0 | Not readable |
| #243A4E text on white | 11.73:1 | AAA | Lc 96.9 | Preferred for body text |
| #243A4E text on black | 1.79:1 | Fails | Lc 0.0 | Not readable |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 900.
-
Step 50
50
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EBF0
oklch(93.7% 0.009 242.8)
-
Step 200
200
#D0DBE5
oklch(88.6% 0.018 245.4)
-
Step 300
300
#B0C3D6
oklch(80.9% 0.034 248.2)
-
Step 400
400
#86A4C1
oklch(70.6% 0.054 247.7)
-
Step 500
500
#678EB1
oklch(63.1% 0.068 246.2)
-
Step 600
600
#4E779D
oklch(55.5% 0.075 247.5)
-
Step 700
700
#3F6486
oklch(49% 0.069 247.4)
-
Step 800
800
#34526D
oklch(42.7% 0.058 246.8)
-
Step 900
900 (this color)
#243A4E
oklch(34% 0.045 247)
-
Step 950
950
#1B2834
oklch(27.1% 0.029 246.9)
#243A4E with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #323A4F | 0.020 |
| Deuteranopia (no green cones) | #2C364E | 0.016 |
| Tritanopia (no blue cones) | #103F41 | 0.038 |
| Achromatopsia (no color) | #383838 | 0.045 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243A4E
#243A4E
oklch(34% 0.045 247)
- #48331E
#48331E
oklch(34% 0.045 65.3)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #243A4E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.007
- Midnight Green #073B4C ΔE 0.025
- Prussian Blue #1D3557 ΔE 0.028
- Gunmetal #293241 ΔE 0.030
- Onyx #343A40 ΔE 0.032
- Charcoal #264653 ΔE 0.039
- Dark Grey Blue #29465B ΔE 0.042
- Space Cadet #2B2D42 ΔE 0.042
Use #243A4E in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.